Good involuntary stability which occurs through repetition of the positive movement…..but HOW?

This video makes the movement seem silly or strange.Why would she be tapping her abdominals and then her lumbar back extensors?Can you figure this out?

She is purely trying to remind her brain of which muscles are required to stabilize the pelvis as she goes into hip extension versus hip flexion. In this video there is added speedbut this only comes once the slow controlled version is achieved.